The steering column tilt assembly for a vehicle includes the housing that accepts a shoe release lever, with a pair of integral trunions, that can be manually attached and pivoted into an operating position without the employment of tools or fixtures.
Steering columns with tilt assemblies have been employed for many years. Vehicle operators find steering wheels with an adjustable height a desirable feature. As a result, most motor vehicles manufactured in North America today have adjustable height steering wheels. Farm machinery such as tractors and self propelled harvesters also have adjustable position steering wheels.
One steering assembly tilt housing that has been manufactured for several years has a shoe release lever that acts upon three springs during operation. One spring urges the shoe release lever toward an unlocked position and toward contact with two tilt lock pivoted shoes. Each of the other two springs bias one of the pivoted shoes toward a locked position. A separate shoe release lever pivot pin pivotally attaches the shoe release lever to the tilt housing.
One of the two pivoted shoes receives a fixed housing pin between two pivoted shoe bars at any given time to lock the tilt housing in a fixed position. The other shoe is held in an unlocked position by contact between the edge of a bar and the fixed housing pin. As a result, each one of the springs that biases a pivoted shoe toward a locked position must exert sufficient force to hold one of the pivoted shoes in a locked position and to simultaneously overcome the force of the one spring that urges the shoe release lever toward an unlocked position.
During assembly of these known steering column tilt assemblies all three springs must be compressed and the passage through the shoe release lever has to be aligned with passages in the tilt housing before the release lever pivot pin can be inserted. It is possible for most individuals to compress all three springs, align the pivot pin apertures and then insert the release lever pivot pin manually. However, the task is time consuming. Due to the stress on the fingers, hands, and arms only a limited number of release lever pivot pins can be installed per day. To relieve the stress that results from manual assembly, fixtures are used which compress the springs and align the apertures when pivotally attaching a shoe release lever to a tilt housing. This use of an assembly fixture reduces strain on assembly personnel but does not significantly reduce tilt housing unit assembly time.
The steering column tilt assembly includes a fixed housing and a tilt housing pivotally attached to the fixed housing for pivotal movement about a tilt axis. A fixed shoe is attached to the fixed housing. A pivoted shoe is pivotally attached to the tilt housing for pivotal movement about a shoe pivot axis that is parallel to the tilt axis. A shoe release lever has a pivoted end shank portion with an integral bottom trunion and an integral top trunion that is coaxial with the integral bottom trunion and a trunion axis, a center section with a shoe wedge surface, and a handle end. A shoe release lever slot is formed in the tilt housing. A release lever bore in the tilt housing includes an upper bore portion on a first side of the shoe release lever slot receives the integral top trunion. A lower bore portion on a second side of the shoe release lever slot that receives the integral bottom trunion. The lower bore portion has an open quadrant that permits passage of the pivoted end shank portion into the shoe release lever slot. At least one spring urges the shoe release lever to pivot about the trunion axis toward a shoe locked position in which the shoe wedge surface engages the pivoted shoe and holds the pivoted shoe in engagement with the fixed shoe.